(CNN)Fifty years ago today, the Ohio National Guard fired on Kent State University students as they protested against the Vietnam War. Four students were killed. Nine were injured.
The incident on May 4, 1970, now known as the Kent State massacre, dramatically changed the nation.
It prompted a nationwide student strike that forced hundreds of colleges and universities to shut down. Life magazine and Newsweek dedicated cover stories to the incident. The New York Times famously showcased the now-iconic photograph of a young woman screaming as she knelt over the body of a Kent State student.